Pump device for dishwasher appliance

ABSTRACT

Dishwasher appliances are provided. A pump device of a dishwasher appliance may include a first centrifugal pump in fluid communication with a drain and a second centrifugal pump in fluid communication with a fluid circulation assembly. The pump device further includes a motor, the motor including a driveshaft, the driveshaft rotatable in a first direction and a second opposite direction. The pump device further includes a first one-way bearing connecting the first centrifugal pump to the driveshaft, the first one-way bearing operable to rotate the impeller of the first centrifugal pump when the driveshaft is rotating in the first direction, and a second one-way bearing connecting the second centrifugal pump to the driveshaft, the second one-way bearing operable to rotate the impeller of the second centrifugal pump when the driveshaft is rotating in the second direction.

FIELD OF THE INVENTION

The subject matter of the present disclosure relates generally to dishwasher appliances, and more particularly to pump devices for circulation and drainage purposes in dishwasher appliances.

BACKGROUND OF THE INVENTION

Dishwasher appliances generally include a tub that defines a wash compartment. Rack assemblies can be mounted within the wash compartment of the tub for receipt of articles for washing. Spray assemblies within the wash compartment can apply or direct wash fluid towards articles disposed within the rack assemblies in order to clean such articles. Multiple spray assemblies can be provided including e.g., a lower spray arm assembly mounted to the tub at a bottom of the wash compartment, a mid-level spray arm assembly mounted to one of the rack assemblies, and/or an upper spray assembly mounted to the tub at a top of the wash compartment. Other configurations may be used as well.

A dishwasher appliance is typically equipped with at least one pump for circulating fluid through the spray assemblies. Many known dishwasher appliances additionally include a separate pump for facilitating drainage of wash fluid from the tub. However, the use of two separate pumps for circulation and drainage purposes has a variety of disadvantages. For example, the use of separate circulation and drainage pumps thus requires the use of two separate motors for operating the respective pumps, which can undesirably increase the number of components in the dishwasher appliance and the associated cost of the dishwasher appliances. Additionally, the use of two motors and two separate pumps can lead to space concerns within the dishwasher appliance. Still further, the use of two separate motors and two separate pumps can cause undesirable vibrations in the dishwasher appliance during operation.

Accordingly, improved dishwasher appliances are desired in the art. In particular, improved pump devices for dishwasher appliances which can reduce space and cost concerns while additionally providing vibration reducing characteristics would be advantageous.

BRIEF DESCRIPTION OF THE INVENTION

In one exemplary embodiment, the present disclosure provides a dishwasher appliance. The dishwasher appliance includes a tub that defines a wash chamber for receipt of articles for washing, a sump for collecting fluid from the wash chamber, a fluid circulation assembly in fluid communication with the sump for circulating fluid in the tub, and a drain for draining fluid from the sump. The dishwasher appliance may further include a pump device in fluid communication with the sump. The pump device includes a first centrifugal pump, the first centrifugal pump comprising an impeller and in fluid communication with the drain, and a second centrifugal pump, the second centrifugal pump comprising an impeller and in fluid communication with the fluid circulation assembly. The pump device further includes a motor, the motor including a driveshaft, the driveshaft rotatable in a first direction and a second opposite direction. The pump device further includes a first one-way bearing connecting the first centrifugal pump to the driveshaft, the first one-way bearing operable to rotate the impeller of the first centrifugal pump when the driveshaft is rotating in the first direction, and a second one-way bearing connecting the second centrifugal pump to the driveshaft, the second one-way bearing operable to rotate the impeller of the second centrifugal pump when the driveshaft is rotating in the second direction.

In another exemplary embodiment, the present disclosure provides a dishwasher appliance. The dishwasher appliance includes a tub that defines a wash chamber for receipt of articles for washing, a sump for collecting fluid from the wash chamber, a fluid circulation assembly in fluid communication with the sump for circulating fluid in the tub, and a drain for draining fluid from the sump. The dishwasher appliance may further include a pump device in fluid communication with the sump. The pump device includes a first pump, the first pump in fluid communication with the drain, and a second pump, the second pump in fluid communication with the fluid circulation assembly. The pump device further includes a motor, the motor including a driveshaft, the driveshaft rotatable in a first direction and a second opposite direction., and a common housing enclosing the first pump, the second pump, and the motor. The pump device further includes a first bulkhead and a second bulkhead disposed in the common housing, the first bulkhead partitioning the first pump from the motor, the second bulkhead partitioning the second pump from the motor. The pump device further includes a first seal disposed in the first bulkhead and a second seal disposed in the second bulkhead, the first pump connected to the motor through the first seal, the second pump connected to the motor through the second seal.

These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

FIG. 1 provides a front view of a dishwasher appliance in accordance with one embodiment of the present disclosure.

FIG. 2 provides a side, cross-sectional view of a dishwasher appliance in accordance with one embodiment of the present disclosure.

FIG. 3 provides a schematic view of a dishwasher appliance in accordance with one embodiment of the present disclosure.

FIG. 4 provides a schematic view of a pump device for a dishwasher appliance in accordance with one embodiment of the present disclosure.

FIG. 5 provides a schematic view of a pump device for a dishwasher appliance in accordance with another embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

As used herein, the term “article” may refer to, but need not be limited to, dishes, pots, pans, silverware, and other cooking utensils and items that can be cleaned in a dishwashing appliance. The term “wash cycle” is intended to refer to one or more periods of time during the cleaning process where a dishwashing appliance operates while containing articles to be washed and uses a detergent and water, preferably with agitation, to e.g., remove soil particles including food and other undesirable elements from the articles. The term “rinse cycle” is intended to refer to one or more periods of time during the cleaning process in which the dishwashing appliance operates to remove residual soil, detergents, and other undesirable elements that were retained by the articles after completion of the wash cycle. The term “drying cycle” is intended to refer to one or more periods of time in which the dishwashing appliance is operated to dry the articles by removing fluids from the wash chamber. The term “fluid” refers to a liquid used for washing and/or rinsing the articles and is typically made up of water that may include additives such as e.g., detergent or other treatments.

FIGS. 1 and 2 depict an exemplary domestic dishwasher 100 that may be configured in accordance with aspects of the present disclosure. For the particular embodiment of FIGS. 1 and 2, the dishwasher 100 includes a cabinet 102 having a tub 104 therein that defines a wash chamber 106. The tub 104 includes a front opening (not shown) and a door 120 hinged at its bottom 122 for movement between a normally closed vertical position (shown in FIGS. 1 and 2), wherein the wash chamber 106 is sealed shut for washing operation, and a horizontal open position for loading and unloading of articles from the dishwasher. Latch 123 is used to lock and unlock door 120 for access to chamber 106.

Upper and lower guide rails 124, 126 are mounted on tub side walls 128 and accommodate roller-equipped rack assemblies 130 and 132. Each of the rack assemblies 130, 132 is fabricated into lattice structures including a plurality of elongated members 134 (for clarity of illustration, not all elongated members making up assemblies 130 and 132 are shown in FIG. 2). Each rack 130, 132 is adapted for movement between an extended loading position (not shown) in which the rack is substantially positioned outside the wash chamber 106, and a retracted position (shown in FIGS. 1 and 2) in which the rack is located inside the wash chamber 106. This is facilitated by rollers 135 and 139, for example, mounted onto racks 130 and 132, respectively. A silverware basket (not shown) may be removably attached to rack assembly 132 for placement of silverware, utensils, and the like, that are otherwise too small to be accommodated by the racks 130, 132.

The dishwasher 100 further includes a lower spray-arm assembly 144 that is rotatably mounted within a lower region 146 of the wash chamber 106 and above a sump 142 so as to rotate in relatively close proximity to rack assembly 132. A mid-level spray-arm assembly 148 is located in an upper region of the wash chamber 106 and may be located in close proximity to upper rack 130. Additionally, an upper spray assembly 150 may be located above the upper rack 130.

The lower and mid-level spray-arm assemblies 144, 148 and the upper spray assembly 150 are part of a fluid circulation assembly 152 for circulating water and dishwasher fluid in the tub 104. As discussed below, fluid circulation assembly 152 may receive fluid from a pump device 200 for circulation of the fluid in the tub 104.

Each spray-arm assembly 144, 148 includes an arrangement of discharge ports or orifices for directing fluid onto dishes or other articles located in rack assemblies 130 and 132. The arrangement of the discharge ports in spray-arm assemblies 144, 148 provides a rotational force by virtue of washing fluid flowing through the discharge ports. The resultant rotation of the spray-arm assemblies 144, 148 and the operation of spray assembly 150 provides coverage of dishes and other dishwasher contents with a washing spray. Other configurations of spray assemblies may be used as well.

Dishwasher assembly 100 further includes a sump 142, which may be provided in lower region 146 below, for example, lower spray-arm assembly 144. Sump 142 generally collects fluid from the wash chamber 106 for circulation within the tub 104, such as back into the wash chamber 106 through fluid circulation assembly 152, as well as drainage from the tub 104 and dishwasher appliance 100 in general. Drainage may occur, for example, through a drain 154 which is provided for draining fluid from the sump 142.

The dishwasher 100 is further equipped with a controller 137 to regulate operation of the dishwasher 100. The controller may include one or more memory devices and one or more microprocessors, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with a cleaning cycle. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor.

The controller 137 may be positioned in a variety of locations throughout dishwasher 100. In the illustrated embodiment, the controller 137 may be located within a control panel area 121 of door 120 as shown in FIGS. 1 and 2. In such an embodiment, input/output (“I/O”) signals may be routed between the control system and various operational components of dishwasher 100 along wiring harnesses that may be routed through the bottom 122 of door 120. Typically, the controller 137 includes a user interface panel/controls 136 through which a user may select various operational features and modes and monitor progress of the dishwasher 100. In one embodiment, the user interface 136 may represent a general purpose I/O (“GPIO”) device or functional block. In one embodiment, the user interface 136 may include input components, such as one or more of a variety of electrical, mechanical or electro-mechanical input devices including rotary dials, push buttons, and touch pads. The user interface 136 may include a display component, such as a digital or analog display device designed to provide operational feedback to a user. The user interface 136 may be in communication with the controller 137 via one or more signal lines or shared communication busses.

It should be appreciated that the invention is not limited to any particular style, model, or configuration of dishwasher. The exemplary embodiment depicted in FIGS. 1 and 2 is for illustrative purposes only. For example, different locations may be provided for user interface 136, different configurations may be provided for racks 130, 132, and other differences may be applied as well.

Referring now to FIGS. 3 through 5, various embodiments of a pump device 200 for use with a dishwasher appliance according to the present disclosure are illustrated. As discussed, sump 142 advantageously collects fluid for circulation and drainage purposes. Pump device 200 is in fluid communication with the sump 142, and advantageously facilitates both circulation and drainage, through selective operation of a single motor connected to two pumps. Additionally, pump device 200 may include various sealing and operating characteristics that provide improved performance relative to known dishwasher appliance pump apparatus, and may further include features that reduce the noise associated with the pump device 200 during operation thereof.

Pump device 200 may include, for example, a motor 202, a first pump 204, and a second pump 206. First pump 204 may generally be in fluid communication with the drain 154, and second pump 206 may generally be in fluid communication with the fluid circulation assembly 152. Motor 202 is generally connected to the first pump 204 and the second pump 206, and is selectively operable to operate the first pump 204 and second pump 206. For example, motor 202 may include a driveshaft 210, which may extend between a first end 212 and a second end 214. Driveshaft 210 may be rotatable in a first direction 216 and a second direction 218 opposite to the first direction 216. Such rotation 216, 218 may be selectively performed based on, for example, commands from the controller 137. First pump 204 and second pump 206 may be connected to driveshaft 210, and each pump may be selectively operable based on rotation of the driveshaft 210 in a certain direction. For example, first pump 204, but not second pump 206, may be operable when the driveshaft 210 is rotating in the first direction 216. Second pump 206, but not first pump 204, may be operable when the driveshaft 210 is rotating in the second direction 218.

As illustrated, in exemplary embodiments, first pump 204 and second pump 206 are disposed on opposing ends of the motor 202. For example, first pump 204 may be adjacent and connected to first end 212 of the driveshaft 210, while second pump 206 may be adjacent and connected to second end 214 of the driveshaft 210.

In exemplary embodiments, first pump 204 and second pump 206 are centrifugal pumps. A centrifugal pump is generally a pump wherein fluid enters a pump impeller along or near a rotating axis and is accelerated by the impeller, flowing radially outward towards and through an outlet of the pump. Centrifugal pumps are particularly advantageous for use in dishwasher appliance 100 applications, due to their low cost and reliability. Additionally, centrifugal pumps are generally more tolerant to, for example, food particles, than other pumps, etc. Alternatively, however, other suitable pumps are within the scope and spirit of the present disclosure. In any case, in some embodiments, first pump 204 and second pump 206 may each include an impeller 220, 222. The impellers 220, 222 may be connected to and selectively rotatable by operation of the driveshaft 210.

As illustrated in FIGS. 4 and 5, one-way bearings 230, 232 may be utilized to facilitate selective operation of the pumps 204, 206 due to operation of the motor 202. A one-way bearing generally engages and rotates a component connected to the one-way bearing when the one-way bearing is rotated in one direction, but does not transmit any rotational force or otherwise engage the component when rotated in an opposite direction. For example, first one-way bearing 230 may connect the first pump 204 to the driveshaft 210. The first one-way bearing 230 may be operable to operate the first pump 204, such as by rotating the first impeller 220, when the driveshaft 210 is rotating in the first direction 216 (but not the second direction 218). Second one-way bearing 232 may connect the second pump 206 to the driveshaft 210. The second one-way bearing 232 may be operable to operate the second pump 206, such as by rotating the second impeller 222, when the driveshaft 210 is rotating in the second direction 218 (but not the first direction 216).

In some embodiments, one-way bearings 230, 232 are sealed bearings, such that external fluids generally cannot access the roller components of the bearings. In alternative embodiments, un-sealed one-way bearings 230, 232 may be utilized.

In exemplary embodiments, pump device 200 may include a common housing 240 in which the motor 202, first pump 204, and second pump 206 may be enclosed. The use of a common housing 240 to enclose these components may provide noise and vibration reduction characteristics to the dishwasher appliance 100. For example, due to the use of a common housing 240, the natural frequency of the pump device 200 is lowered relative to if these components were not enclosed in a common housing. Lowering of the natural frequency can reduce the noise and vibration of the dishwasher appliance 100 during operation thereof. Additionally, counterweights or other components are not required in the dishwasher appliance 100 to attempt to reduce noise and vibration, because these reductions are accomplished through use of the common housing 240.

Within common housing 240, bulkheads 242, 244 may partition the pumps 204, 206 and motor 202 from each other. For example, first bulkhead 242 disposed in the common housing 240 may partition the first pump 204 from the motor 202. Second bulkhead 244 disposed in the common housing 240 may partition the second pump 206 from the motor 202.

Further, the connection of the pumps 204, 206 to the motor 202 may extend through the bulkheads 242, 244. For example, a first seal 252 may be disposed in the first bulkhead 242 and a second seal 254 may be disposed in the second bulkhead 244. The first pump 204 may be connected to the motor 202 through the first seal 252, and the second pump 206 may be connected to the motor 202 through the second seal 254. Seals 252, 254 may be any suitable seals. For example, lip seals, such as those formed from plastic or rubber, may be utilized. Alternatively, mechanical seals, such as face seals with spring elements, may be utilized. Further, o-rings and any other suitable sealing apparatus are within the scope and spirit of the present disclosure. The use of seals 252, 254 in pump devices 100 according to the present disclosure may be particularly advantageous by improving the performance of the pump devices 100 in general. For example, seals 252, 254 may allow a common housing 240 to be utilized, while preventing motor 202 from encountering fluid during operation. Motor 202 may thus not require an individual fluid-tight housing, and may operate efficiently in a generally dry environment.

In some embodiments as illustrated in FIG. 5, the driveshaft 210 may extend through the seals 252, 254. Driveshaft 210 may, for example, be directly connected to pumps 204, 206 through bearings 230, 232. In other words, driveshaft 210 may be a common driveshaft 210 for the motor 202 and pumps 202, 204. Alternatively, pump device 200 may further include a first coupling shaft 256 and a second coupling shaft 258. The driveshaft 210 may be directly connected to the coupling shafts 256, 258 through bearings 230, 232, and the coupling shafts 256, 258 may connect to the pumps 204, 206. Bearings 230, 232 may, for example, be press-fit into the first coupling shaft 256 and second coupling shaft 258, respectively. As illustrated in FIG. 4, the coupling shafts 256, 258 may extend through the respective seals 252, 254.

In some embodiments, as shown for example in FIG. 5, bearings 230, 232 may be disposed in first and second pump compartments 264, 266 of the common housing 240 that are defined by the bulkheads 242, 244. Such compartments 264, 266 may generally allow fluid flow therein, such that in some embodiments bearings 230, 232 may be sealed bearings as discussed herein. First pump compartment 264 may define a fluid inlet 272 and a fluid outlet 274, and second pump compartment 266 may define a fluid inlet 276 and a fluid outlet 278. Fluid inlets 272, 276 may be in fluid communication with the sump 142, such that fluid may flow through either inlet 272, 276 depending on the desired output location of the fluid. Fluid outlet 274 may be in fluid communication with the drain 154, while fluid outlet 278 may be in fluid communication with the fluid circulation assembly 152.

A motor compartment 262 may additionally be defined by the bulkheads 242, 244. In some embodiments, as shown for example in FIG. 4, bearings 230, 232 may be disposed in motor compartment 262. As discussed, motor compartment 262 may be partitioned form the first and second pump compartments 264, 266, such that fluid from these compartments 264, 266 may generally not access the motor compartment 262. Thus, in some embodiments, bearings 230, 232 may be unsealed bearings as discussed herein.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. 

What is claimed is:
 1. A dishwasher appliance, comprising: a tub that defines a wash chamber for receipt of articles for washing; a sump for collecting fluid from the wash chamber; a fluid circulation assembly in fluid communication with the sump for circulating fluid in the tub; a drain for draining fluid from the sump; and a pump device in fluid communication with the sump, the pump device comprising: a first centrifugal pump, the first centrifugal pump comprising an impeller and in fluid communication with the drain; a second centrifugal pump, the second centrifugal pump comprising an impeller and in fluid communication with the fluid circulation assembly; a motor, the motor comprising a driveshaft, the driveshaft rotatable in a first direction and a second opposite direction; a first one-way bearing connecting the first centrifugal pump to the driveshaft, the first one-way bearing operable to rotate the impeller of the first centrifugal pump when the driveshaft is rotating in the first direction; and a second one-way bearing connecting the second centrifugal pump to the driveshaft, the second one-way bearing operable to rotate the impeller of the second centrifugal pump when the driveshaft is rotating in the second direction.
 2. The dishwasher appliance of claim 1, wherein the first centrifugal pump, the second centrifugal pump, and the motor are enclosed in a common housing.
 3. The dishwasher appliance of claim 2, further comprising a first bulkhead and a second bulkhead disposed in the common housing, the first bulkhead partitioning the first centrifugal pump from the motor, the second bulkhead partitioning the second centrifugal pump from the motor.
 4. The dishwasher appliance of claim 3, further comprising a first seal disposed in the first bulkhead and a second seal disposed in the second bulkhead, the first centrifugal pump connected to the motor through the first seal, the second centrifugal pump connected to the motor through the second seal.
 5. The dishwasher appliance of claim 3, wherein the driveshaft extends through the first seal and the second seal.
 6. The dishwasher appliance of claim 3, further comprising a first coupling shaft and a second coupling shaft, the first coupling shaft extending through the first seal and connecting the impeller of the first centrifugal pump to the driveshaft, the second coupling shaft extending through the second seal and connecting the impeller of the second centrifugal pump to the driveshaft.
 7. The dishwasher appliance of claim 6, wherein the first one-way bearing is press-fit into the first coupling shaft and the second one-way bearing is press-fit into the second coupling shaft.
 8. The dishwasher appliance of claim 3, wherein the first one-way bearing and second one-way bearing are disposed in a motor compartment of the common housing defined by the first bulkhead and second bulkhead.
 9. The dishwasher appliance of claim 3, wherein the first one-way bearing is disposed in a first pump compartment of the common housing defined by the first bulkhead and the second one-way bearing is disposed in a second pump compartment defined by the second bulkhead.
 10. The dishwasher appliance of claim 3, wherein the first one-way bearing and second one-way bearing are sealed.
 11. A dishwasher appliance, comprising: a tub that defines a wash chamber for receipt of articles for washing; a sump for collecting fluid from the wash chamber; a fluid circulation assembly in fluid communication with the sump for circulating fluid in the tub; a drain for draining fluid from the sump; and a pump device in fluid communication with the sump, the pump device comprising: a first pump, the first pump in fluid communication with the drain; a second pump, the second pump in fluid communication with the fluid circulation assembly; a motor, the motor comprising a driveshaft, the driveshaft rotatable in a first direction and a second opposite direction; a common housing enclosing the first pump, the second pump, and the motor; a first bulkhead and a second bulkhead disposed in the common housing, the first bulkhead partitioning the first pump from the motor, the second bulkhead partitioning the second pump from the motor; and a first seal disposed in the first bulkhead and a second seal disposed in the second bulkhead, the first pump connected to the motor through the first seal, the second pump connected to the motor through the second seal.
 12. The dishwasher appliance of claim 11, wherein the pump device further comprises: a first one-way bearing connecting the first pump to the driveshaft, the first one-way bearing operating the first pump when the driveshaft is rotating in the first direction; and a second one-way bearing connecting the second pump to the driveshaft, the second one-way bearing operating the second pump when the driveshaft is rotating in the second direction.
 13. The dishwasher appliance of claim 12, wherein the first one-way bearing and second one-way bearing are disposed in a motor compartment of the common housing defined by the first bulkhead and second bulkhead.
 14. The dishwasher appliance of claim 12, wherein the first one-way bearing is disposed in a first pump compartment of the common housing defined by the first bulkhead and the second one-way bearing is disposed in a second pump compartment defined by the second bulkhead.
 15. The dishwasher appliance of claim 12, wherein the first one-way bearing and second one-way bearing are sealed.
 16. The dishwasher appliance of claim 11, wherein the first pump and the second pump are centrifugal pumps.
 17. The dishwasher appliance of claim 11, wherein the driveshaft extends through the first seal and the second seal.
 18. The dishwasher appliance of claim 11, further comprising a first coupling shaft and a second coupling shaft, the first coupling shaft extending through the first seal and connecting the first pump to the driveshaft, the second coupling shaft extending through the second seal and connecting the second pump to the driveshaft.
 19. The dishwasher appliance of claim 15, wherein a first one-way bearing is press-fit into the first coupling shaft and a second one-way bearing is press-fit into the second coupling shaft. 